Used to be, every time I would suffer one of those resets that blows away my preferences, I'd restore my Saved Preferences file and discover, like you have, that my network services had multiplied. Finally, I realized that if I restored my NetworkDB file too, that wouldn't happen.

If you haven't created any network services of your own (and don't have a backup of a good copy of your NetworkDB file to restore), the easiest way to fix your current dilemma is to delete the NetworkDB file (with FileZ) and perform a soft reset - a new NetworkDB with single instances should then be created from your SIM.

If you have created some network services of your own:
1. Launch FileZ, select NetworkDB and choose Edit from the menu.
2. The records are numbered such that the first one is "0".
3. Select the first record and tap View
4. The name of the profile should appear somewhere on the right side of the window; if this isn't one of your GPRS records, go to the next one.
5. Your two duplicated records should be listed together; after you find the first one, back out and check the next one. If it's the duplicate, back out, highlight it and tap Delete.